1. Field of the Invention
The present invention relates to a photographic material developing apparatus including processing tanks, and rack units removably mounted in the processing tanks, respectively, each rack unit having a pair of guide members with a variable distance therebetween for guiding a photographic material passing through the processing tanks. More particularly, the invention relates to these rack units.
2. Description of the Related Art
In a photographic material developing apparatus as noted above, the rack units transport a photographic material such as exposed film or exposed printing paper successively through a plurality of processing ranks storing different processing liquids to develop the photographic material.
U.S. Pat. No. 4,903,064, for example, discloses such rack units each including a guide width varying mechanism for adjusting a distance between a pair of guide members, a first drive line for transmitting power from an external drive source, a second drive line connected to the guide width varying mechanism for driving the latter with the power received from the first drive line, and a coupling for enabling and disabling power transmission from the first drive line to the second drive line. The coupling has a connecting member connectable to a connected member included in the first drive line. The connecting member is connected to the second drive line.
Different types of photographic materials have different widths. It is therefore necessary to adjust a photographic material passage width, i.e. the distance (guide width) between the pair of guide members, to suit a photographic material to be transported. Thus, each rack unit includes the guide width varying mechanism for varying a relative position between the pair of guide members. i.e. a guide width. The relative positions between the pairs of guide members in all of the rack units mounted in the processing tanks are adjusted to a passage width of the photographic material to be transported.
For inspection, adjustment or the like, it is necessary to withdraw the rack units from the processing tanks. Therefore, the rack units are removably mounted in the processing tanks. The processing tanks have a drive line for simultaneously driving the guide width varying mechanisms of the rack units. When the rack units are placed in the processing tanks, this drive line is drivingly connected through the coupling to a drive line of each rack unit for driving the guide width varying mechanism.
However, when one of the rack units is withdrawn from the processing tank and the guide width varying mechanism is inspected or adjusted, the relative position between the pair of guide members may be varied. It is therefore necessary, when placing this rack unit back in the processing tank, to connect the drive lines while adjusting the relative position between the pair of guide members to agree with the relative positions between the pairs of guide members in the other rack units remaining in the processing tanks. This adjusting and connecting operation is quite troublesome.